To mark the occasion, her mother Victoria shared a video of Estelle with her brother Oscar skiing on the royal account.

Their pet nicknamed Rio joined the family.

"Today is Her Royal Highness Princess Estelle's 12th birthday. Congratulations!"

- says the caption on Instagram.

This trip to the mountains probably took place before the visit of Crown Princess Victoria and Prince Daniel to the USA.

The pair made a three-day visit to California with Swedish Minister of State Johan Forsel to develop the country's relationship with the American state.

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And we showed you four stylish outfits that Crown Princess Victoria showed off in public when she visited the United States.